1. Field of the Invention
The present invention relates to an organic electroluminescent device and to an electronic apparatus having the organic electroluminescent device.
Priority is claimed on Japanese Patent Application No. 2003-126316, filed May 1, 2003, the content of which is incorporated herein by reference.
2. Description of Related Art
Currently, display devices must be capable of displaying color images. In general, in order to display color images, plural sets of three kinds of dots, i.e., plural sets of red, green, and blue dots, which respectively emit red light (R), green light (G), and blue light (B), as minimum displaying units (sub-pixels), are used. These three kinds of dots form one pixel which is a minimum unit for color displaying.
As arrangement patterns of such dots (sub-pixels) for forming pixels, a stripe pattern shown in FIG. 12A, a mosaic pattern shown in FIG. 12B, and a delta pattern shown in FIG. 12C, are known in the art.
In addition, another arrangement pattern, in which four dots (cells), each of which emits one of red light (R), green light (G), and blue light (B), are arranged in a substantially four-dot (cell) matrix pattern for forming one pixel, is also known in the art (see, for example, Japanese Unexamined Patent Application, First Publication No. Hei 06-102503).
The above-mentioned stripe pattern, mosaic pattern, delta pattern, and the pattern in which four dots (cells) are arranged in a substantially matrix pattern, have been basically conceived to facilitate control of driving each of the dots. In particular, in the case of the stripe pattern, mosaic pattern, and delta pattern, substantially the same quantities of red, green, and blue dots are arranged overall, as well as in each of the pixels, and thereby the driving method for the pixels is simplified.
However, in view of perception, it is not suitable for the human visual system to form each of the pixels so as to include the same quantities of red, green, and blue dots.
More specifically, in the case of human beings, the capability of distinguishing colors resides in the light sense organ in the macula lutea of the eyes, and retina cones which detect colored light are classified into three types, i.e., S-type, L-type, and M-type, respectively corresponding to blue color, red color, and green color. When observing a micrograph of the macula lutea, the retina cones are observed as spots which are distinguishable from each other. Assuming that the quantities of the red and green retina cones are “10”, the quantity of the blue retina cones is only “1” on average; therefore, the relative ratio among the red retina cones, the green retina cones, and the blue retina cones, is 10:10:1.
Accordingly, the detailed visual information is detected (visually sensed) by (i.e., resolution is determined by) primarily the red and green retina cones, and the blue retina cones are not elements for detecting detailed visual information even though they are elements for distinguishing colors.
In the case of a pattern in which four dots (cells) are arranged in the substantially matrix pattern, for example, the quantity of the blue sub-pixels can be increased; however, it is difficult to improve the resolution since this arrangement is basically conceived to facilitate the drive control operation. Moreover, this technology is, in particular, applied to display devices such as a plasma display, a CRT (Cathode Ray Tube), a liquid crystal display, a fluorescent display tube, an electroluminescent display, and a light emitting diode display. In recent years, organic electroluminescent displays have been remarkably developed; however, the application to organic electroluminescent devices is not considered in the above-mentioned technology.